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<FONT color="green">001</FONT>    package metaface.client;<a name="line.1"></a>
<FONT color="green">002</FONT>    <a name="line.2"></a>
<FONT color="green">003</FONT>    import java.net.*;<a name="line.3"></a>
<FONT color="green">004</FONT>    import java.io.*;<a name="line.4"></a>
<FONT color="green">005</FONT>    import java.util.*;<a name="line.5"></a>
<FONT color="green">006</FONT>    <a name="line.6"></a>
<FONT color="green">007</FONT>    /**<a name="line.7"></a>
<FONT color="green">008</FONT>     *  Implementation of a basic HTTP client for Firewall tunneling. The client<a name="line.8"></a>
<FONT color="green">009</FONT>     *  supports both Client->Server and Server->Client communication.<a name="line.9"></a>
<FONT color="green">010</FONT>     *<a name="line.10"></a>
<FONT color="green">011</FONT>     *@author     Simon Beard <a name="line.11"></a>
<FONT color="green">012</FONT>     *@version    1.0<a name="line.12"></a>
<FONT color="green">013</FONT>     */<a name="line.13"></a>
<FONT color="green">014</FONT>    public class HTTPClient implements Runnable {<a name="line.14"></a>
<FONT color="green">015</FONT>            /**<a name="line.15"></a>
<FONT color="green">016</FONT>             *  Description of the Field<a name="line.16"></a>
<FONT color="green">017</FONT>             */<a name="line.17"></a>
<FONT color="green">018</FONT>            public final static int PENDING = 1;<a name="line.18"></a>
<FONT color="green">019</FONT>            /**<a name="line.19"></a>
<FONT color="green">020</FONT>             *  Description of the Field<a name="line.20"></a>
<FONT color="green">021</FONT>             */<a name="line.21"></a>
<FONT color="green">022</FONT>            public final static int DATA = 2;<a name="line.22"></a>
<FONT color="green">023</FONT>            /**<a name="line.23"></a>
<FONT color="green">024</FONT>             *  The server URL<a name="line.24"></a>
<FONT color="green">025</FONT>             */<a name="line.25"></a>
<FONT color="green">026</FONT>            private String _url;<a name="line.26"></a>
<FONT color="green">027</FONT>            /**<a name="line.27"></a>
<FONT color="green">028</FONT>             *  Pending connection thread<a name="line.28"></a>
<FONT color="green">029</FONT>             */<a name="line.29"></a>
<FONT color="green">030</FONT>            private Thread _pendingTID;<a name="line.30"></a>
<FONT color="green">031</FONT>            /**<a name="line.31"></a>
<FONT color="green">032</FONT>             *  Notify to stop client<a name="line.32"></a>
<FONT color="green">033</FONT>             */<a name="line.33"></a>
<FONT color="green">034</FONT>            private boolean _stop;<a name="line.34"></a>
<FONT color="green">035</FONT>            /**<a name="line.35"></a>
<FONT color="green">036</FONT>             *  Listeners for incoming messages<a name="line.36"></a>
<FONT color="green">037</FONT>             */<a name="line.37"></a>
<FONT color="green">038</FONT>            private HTTPListener _listener;<a name="line.38"></a>
<FONT color="green">039</FONT>            /**<a name="line.39"></a>
<FONT color="green">040</FONT>             *  Input stream for messages<a name="line.40"></a>
<FONT color="green">041</FONT>             */<a name="line.41"></a>
<FONT color="green">042</FONT>            private DataInputStream input;<a name="line.42"></a>
<FONT color="green">043</FONT>            /**<a name="line.43"></a>
<FONT color="green">044</FONT>             *  The connection to the MetaFace HTTP server<a name="line.44"></a>
<FONT color="green">045</FONT>             */<a name="line.45"></a>
<FONT color="green">046</FONT>            private HttpURLConnection connection;<a name="line.46"></a>
<FONT color="green">047</FONT>            /**<a name="line.47"></a>
<FONT color="green">048</FONT>             *  Length of the message<a name="line.48"></a>
<FONT color="green">049</FONT>             */<a name="line.49"></a>
<FONT color="green">050</FONT>            private int length;<a name="line.50"></a>
<FONT color="green">051</FONT>    <a name="line.51"></a>
<FONT color="green">052</FONT>            /**<a name="line.52"></a>
<FONT color="green">053</FONT>             *  Whether data is pending<a name="line.53"></a>
<FONT color="green">054</FONT>             */<a name="line.54"></a>
<FONT color="green">055</FONT>            public boolean pending = false;<a name="line.55"></a>
<FONT color="green">056</FONT>    <a name="line.56"></a>
<FONT color="green">057</FONT>    <a name="line.57"></a>
<FONT color="green">058</FONT>            /**<a name="line.58"></a>
<FONT color="green">059</FONT>             *  Creates a new HTTPClient instance configured to connect to the server<a name="line.59"></a>
<FONT color="green">060</FONT>             *  specified in the url parameter.<a name="line.60"></a>
<FONT color="green">061</FONT>             *<a name="line.61"></a>
<FONT color="green">062</FONT>             *@param  url  URL of the server, example http://bogus:9000<a name="line.62"></a>
<FONT color="green">063</FONT>             */<a name="line.63"></a>
<FONT color="green">064</FONT>            public HTTPClient(String url) {<a name="line.64"></a>
<FONT color="green">065</FONT>                    File[] list;<a name="line.65"></a>
<FONT color="green">066</FONT>                    int i;<a name="line.66"></a>
<FONT color="green">067</FONT>                    File f;<a name="line.67"></a>
<FONT color="green">068</FONT>    <a name="line.68"></a>
<FONT color="green">069</FONT>                    HttpURLConnection connection;<a name="line.69"></a>
<FONT color="green">070</FONT>    <a name="line.70"></a>
<FONT color="green">071</FONT>                    _url = url;<a name="line.71"></a>
<FONT color="green">072</FONT>                    _pendingTID = new Thread(this);<a name="line.72"></a>
<FONT color="green">073</FONT>                    _pendingTID.setPriority(Thread.MAX_PRIORITY);<a name="line.73"></a>
<FONT color="green">074</FONT>                    _listener = null;<a name="line.74"></a>
<FONT color="green">075</FONT>            }<a name="line.75"></a>
<FONT color="green">076</FONT>    <a name="line.76"></a>
<FONT color="green">077</FONT>    <a name="line.77"></a>
<FONT color="green">078</FONT>            /**<a name="line.78"></a>
<FONT color="green">079</FONT>             *  Removes the HTTPListener. The pending connection is stopped, so the client<a name="line.79"></a>
<FONT color="green">080</FONT>             *  won't receive any more messages from the server<a name="line.80"></a>
<FONT color="green">081</FONT>             *<a name="line.81"></a>
<FONT color="green">082</FONT>             *@param  l  HTTPListener to remove<a name="line.82"></a>
<FONT color="green">083</FONT>             */<a name="line.83"></a>
<FONT color="green">084</FONT>            public void removeHTTPListener(HTTPListener l) {<a name="line.84"></a>
<FONT color="green">085</FONT>                    if (_listener != null) {<a name="line.85"></a>
<FONT color="green">086</FONT>                            synchronized (this) {<a name="line.86"></a>
<FONT color="green">087</FONT>                                    _stop = true;<a name="line.87"></a>
<FONT color="green">088</FONT>                            }<a name="line.88"></a>
<FONT color="green">089</FONT>                            _pendingTID.destroy();<a name="line.89"></a>
<FONT color="green">090</FONT>                            _listener = null;<a name="line.90"></a>
<FONT color="green">091</FONT>                    }<a name="line.91"></a>
<FONT color="green">092</FONT>            }<a name="line.92"></a>
<FONT color="green">093</FONT>    <a name="line.93"></a>
<FONT color="green">094</FONT>    <a name="line.94"></a>
<FONT color="green">095</FONT>            /**<a name="line.95"></a>
<FONT color="green">096</FONT>             *  Adds the HTTPListener. The pending connection is started, so the client<a name="line.96"></a>
<FONT color="green">097</FONT>             *  will receive messages from the server.<a name="line.97"></a>
<FONT color="green">098</FONT>             *<a name="line.98"></a>
<FONT color="green">099</FONT>             *@param  l                           HTTPListener to remove<a name="line.99"></a>
<FONT color="green">100</FONT>             *@throws  TooManyListenersException  Thrown if more then one HTTPListener is<a name="line.100"></a>
<FONT color="green">101</FONT>             *      added.<a name="line.101"></a>
<FONT color="green">102</FONT>             */<a name="line.102"></a>
<FONT color="green">103</FONT>            public void addHTTPListener(HTTPListener l) throws TooManyListenersException {<a name="line.103"></a>
<FONT color="green">104</FONT>                    if (_listener == null) {<a name="line.104"></a>
<FONT color="green">105</FONT>                            _listener = l;<a name="line.105"></a>
<FONT color="green">106</FONT>                            synchronized (this) {<a name="line.106"></a>
<FONT color="green">107</FONT>                                    _stop = false;<a name="line.107"></a>
<FONT color="green">108</FONT>                            }<a name="line.108"></a>
<FONT color="green">109</FONT>                            _pendingTID.start();<a name="line.109"></a>
<FONT color="green">110</FONT>                    } else {<a name="line.110"></a>
<FONT color="green">111</FONT>                            throw new TooManyListenersException();<a name="line.111"></a>
<FONT color="green">112</FONT>                    }<a name="line.112"></a>
<FONT color="green">113</FONT>            }<a name="line.113"></a>
<FONT color="green">114</FONT>    <a name="line.114"></a>
<FONT color="green">115</FONT>    <a name="line.115"></a>
<FONT color="green">116</FONT>            /**<a name="line.116"></a>
<FONT color="green">117</FONT>             *  Convience method to send the PENDING connection to the server<a name="line.117"></a>
<FONT color="green">118</FONT>             *<a name="line.118"></a>
<FONT color="green">119</FONT>             *@return               void<a name="line.119"></a>
<FONT color="green">120</FONT>             *@throws  IOException  Thrown if a problem occurs while setting up the pending<a name="line.120"></a>
<FONT color="green">121</FONT>             *      message.<a name="line.121"></a>
<FONT color="green">122</FONT>             */<a name="line.122"></a>
<FONT color="green">123</FONT>            private HttpURLConnection _sendPending() throws IOException {<a name="line.123"></a>
<FONT color="green">124</FONT>                    URL url = new URL(_url);<a name="line.124"></a>
<FONT color="green">125</FONT>                    connection = (HttpURLConnection) url.openConnection();<a name="line.125"></a>
<FONT color="green">126</FONT>                    connection.setUseCaches(false);<a name="line.126"></a>
<FONT color="green">127</FONT>                    connection.setDoOutput(true);<a name="line.127"></a>
<FONT color="green">128</FONT>                    connection.setRequestProperty("Keep-Alive", "timeout=300, max=300");<a name="line.128"></a>
<FONT color="green">129</FONT>                    return connection;<a name="line.129"></a>
<FONT color="green">130</FONT>            }<a name="line.130"></a>
<FONT color="green">131</FONT>    <a name="line.131"></a>
<FONT color="green">132</FONT>    <a name="line.132"></a>
<FONT color="green">133</FONT>            /**<a name="line.133"></a>
<FONT color="green">134</FONT>             *  Thread used to maintain the pending connection<a name="line.134"></a>
<FONT color="green">135</FONT>             */<a name="line.135"></a>
<FONT color="green">136</FONT>            public void run() {<a name="line.136"></a>
<FONT color="green">137</FONT>                    int id;<a name="line.137"></a>
<FONT color="green">138</FONT>                    try {<a name="line.138"></a>
<FONT color="green">139</FONT>                            connection = _sendPending();<a name="line.139"></a>
<FONT color="green">140</FONT>                            DataOutputStream output = new DataOutputStream(connection.getOutputStream());<a name="line.140"></a>
<FONT color="green">141</FONT>                            output.writeInt(PENDING);<a name="line.141"></a>
<FONT color="green">142</FONT>                            output.flush();<a name="line.142"></a>
<FONT color="green">143</FONT>                            output.close();<a name="line.143"></a>
<FONT color="green">144</FONT>                            output = null;<a name="line.144"></a>
<FONT color="green">145</FONT>    <a name="line.145"></a>
<FONT color="green">146</FONT>                            int code = ((HttpURLConnection) connection).getResponseCode();<a name="line.146"></a>
<FONT color="green">147</FONT>    <a name="line.147"></a>
<FONT color="green">148</FONT>                            switch (code) {<a name="line.148"></a>
<FONT color="green">149</FONT>                                                            case 200:<a name="line.149"></a>
<FONT color="green">150</FONT>                                                            {<a name="line.150"></a>
<FONT color="green">151</FONT>                                                                    // HTTP_OK<a name="line.151"></a>
<FONT color="green">152</FONT>                                                                    input = new DataInputStream(connection.getInputStream());<a name="line.152"></a>
<FONT color="green">153</FONT>                                                                    length = input.readInt();<a name="line.153"></a>
<FONT color="green">154</FONT>                                                                    byte buffer[] = new byte[length];<a name="line.154"></a>
<FONT color="green">155</FONT>    <a name="line.155"></a>
<FONT color="green">156</FONT>                                                                    //Read data<a name="line.156"></a>
<FONT color="green">157</FONT>                                                                    if (length >= 0) {<a name="line.157"></a>
<FONT color="green">158</FONT>                                                                            input.readFully(buffer);<a name="line.158"></a>
<FONT color="green">159</FONT>                                                                            if (buffer.length == length) {<a name="line.159"></a>
<FONT color="green">160</FONT>                                                                                    if (_listener != null) {<a name="line.160"></a>
<FONT color="green">161</FONT>                                                                                            _listener.service(buffer, MetaFaceHTTPClient.START);<a name="line.161"></a>
<FONT color="green">162</FONT>                                                                                            pending = true;<a name="line.162"></a>
<FONT color="green">163</FONT>                                                                                    }<a name="line.163"></a>
<FONT color="green">164</FONT>                                                                            } else {<a name="line.164"></a>
<FONT color="green">165</FONT>                                                                                    System.err.println("Short read");<a name="line.165"></a>
<FONT color="green">166</FONT>                                                                            }<a name="line.166"></a>
<FONT color="green">167</FONT>                                                                            buffer = null;<a name="line.167"></a>
<FONT color="green">168</FONT>                                                                    } else {<a name="line.168"></a>
<FONT color="green">169</FONT>                                                                            System.err.println("Invalid length: " + length);<a name="line.169"></a>
<FONT color="green">170</FONT>                                                                    }<a name="line.170"></a>
<FONT color="green">171</FONT>                                                                    break;<a name="line.171"></a>
<FONT color="green">172</FONT>                                                            }<a name="line.172"></a>
<FONT color="green">173</FONT>                                                            case 504:<a name="line.173"></a>
<FONT color="green">174</FONT>                                                            {<a name="line.174"></a>
<FONT color="green">175</FONT>                                                                    //HTTP_GATEWAY_TIMEOUT<a name="line.175"></a>
<FONT color="green">176</FONT>                                                                    System.out.println("error response");<a name="line.176"></a>
<FONT color="green">177</FONT>                                                                    break;<a name="line.177"></a>
<FONT color="green">178</FONT>                                                            }<a name="line.178"></a>
<FONT color="green">179</FONT>                                                            default:<a name="line.179"></a>
<FONT color="green">180</FONT>                                                            {<a name="line.180"></a>
<FONT color="green">181</FONT>                                                                    //OTHER HTTP_SERVER ERRORS<a name="line.181"></a>
<FONT color="green">182</FONT>                                                                    System.out.println("Invalid code:" + code);<a name="line.182"></a>
<FONT color="green">183</FONT>                                                                    break;<a name="line.183"></a>
<FONT color="green">184</FONT>                                                            }<a name="line.184"></a>
<FONT color="green">185</FONT>                            }<a name="line.185"></a>
<FONT color="green">186</FONT>    <a name="line.186"></a>
<FONT color="green">187</FONT>                            //Main loop for receiving messages<a name="line.187"></a>
<FONT color="green">188</FONT>                            while (true) {<a name="line.188"></a>
<FONT color="green">189</FONT>                                    if (input.available() > 0) {<a name="line.189"></a>
<FONT color="green">190</FONT>                                            id = (int) input.readByte();<a name="line.190"></a>
<FONT color="green">191</FONT>                                            length = input.readInt();<a name="line.191"></a>
<FONT color="green">192</FONT>                                            byte buffer[] = new byte[length];<a name="line.192"></a>
<FONT color="green">193</FONT>                                            if (length >= 0) {<a name="line.193"></a>
<FONT color="green">194</FONT>                                                    input.readFully(buffer);<a name="line.194"></a>
<FONT color="green">195</FONT>                                                    if (buffer.length == length) {<a name="line.195"></a>
<FONT color="green">196</FONT>                                                            if (_listener != null) {<a name="line.196"></a>
<FONT color="green">197</FONT>                                                                    _listener.service(buffer, id);<a name="line.197"></a>
<FONT color="green">198</FONT>                                                            }<a name="line.198"></a>
<FONT color="green">199</FONT>                                                    } else {<a name="line.199"></a>
<FONT color="green">200</FONT>                                                            System.err.println("Short read");<a name="line.200"></a>
<FONT color="green">201</FONT>                                                    }<a name="line.201"></a>
<FONT color="green">202</FONT>                                                    buffer = null;<a name="line.202"></a>
<FONT color="green">203</FONT>                                            }<a name="line.203"></a>
<FONT color="green">204</FONT>                                    } else {<a name="line.204"></a>
<FONT color="green">205</FONT>    <a name="line.205"></a>
<FONT color="green">206</FONT>                                            //Sleep to allow other threads to execute<a name="line.206"></a>
<FONT color="green">207</FONT>                                            Thread.yield();<a name="line.207"></a>
<FONT color="green">208</FONT>                                            Thread.sleep(5);<a name="line.208"></a>
<FONT color="green">209</FONT>                                    }<a name="line.209"></a>
<FONT color="green">210</FONT>                            }<a name="line.210"></a>
<FONT color="green">211</FONT>                    } catch (Exception e) {<a name="line.211"></a>
<FONT color="green">212</FONT>                            System.err.println("Exiting " + e);<a name="line.212"></a>
<FONT color="green">213</FONT>                            e.printStackTrace();<a name="line.213"></a>
<FONT color="green">214</FONT>                    }<a name="line.214"></a>
<FONT color="green">215</FONT>            }<a name="line.215"></a>
<FONT color="green">216</FONT>    <a name="line.216"></a>
<FONT color="green">217</FONT>    <a name="line.217"></a>
<FONT color="green">218</FONT>            /**<a name="line.218"></a>
<FONT color="green">219</FONT>             *  Sends a message to the server<a name="line.219"></a>
<FONT color="green">220</FONT>             *<a name="line.220"></a>
<FONT color="green">221</FONT>             *@param  data          Array of bytes to send<a name="line.221"></a>
<FONT color="green">222</FONT>             *@throws  IOException  Thrown if a problem occurs while sending the message<a name="line.222"></a>
<FONT color="green">223</FONT>             */<a name="line.223"></a>
<FONT color="green">224</FONT>            public synchronized void send(byte data[]) throws IOException {<a name="line.224"></a>
<FONT color="green">225</FONT>                    byte buffer[];<a name="line.225"></a>
<FONT color="green">226</FONT>    <a name="line.226"></a>
<FONT color="green">227</FONT>                    // Establish a connection<a name="line.227"></a>
<FONT color="green">228</FONT>                    URL url = new URL(_url);<a name="line.228"></a>
<FONT color="green">229</FONT>                    HttpURLConnection connection = (HttpURLConnection) url.openConnection();<a name="line.229"></a>
<FONT color="green">230</FONT>                    connection.setUseCaches(false);<a name="line.230"></a>
<FONT color="green">231</FONT>                    connection.setDoOutput(true);<a name="line.231"></a>
<FONT color="green">232</FONT>    <a name="line.232"></a>
<FONT color="green">233</FONT>                    // Write out the data<a name="line.233"></a>
<FONT color="green">234</FONT>                    DataOutputStream dataOut = new DataOutputStream(new BufferedOutputStream(connection.getOutputStream()));<a name="line.234"></a>
<FONT color="green">235</FONT>                    dataOut.writeInt(HTTPClient.DATA);<a name="line.235"></a>
<FONT color="green">236</FONT>                    dataOut.writeInt(data.length);<a name="line.236"></a>
<FONT color="green">237</FONT>                    dataOut.write(data);<a name="line.237"></a>
<FONT color="green">238</FONT>                    dataOut.flush();<a name="line.238"></a>
<FONT color="green">239</FONT>                    dataOut.close();<a name="line.239"></a>
<FONT color="green">240</FONT>    <a name="line.240"></a>
<FONT color="green">241</FONT>                    DataInputStream input = new DataInputStream(new BufferedInputStream(connection.getInputStream()));<a name="line.241"></a>
<FONT color="green">242</FONT>                    int type = input.readInt();<a name="line.242"></a>
<FONT color="green">243</FONT>                    if (type == HTTPClient.DATA) {<a name="line.243"></a>
<FONT color="green">244</FONT>                            length = input.readInt();<a name="line.244"></a>
<FONT color="green">245</FONT>                            buffer = new byte[length];<a name="line.245"></a>
<FONT color="green">246</FONT>                            input.readFully(buffer);<a name="line.246"></a>
<FONT color="green">247</FONT>                    } else {<a name="line.247"></a>
<FONT color="green">248</FONT>                            buffer = null;<a name="line.248"></a>
<FONT color="green">249</FONT>                            throw new IOException("Unknown Response Type");<a name="line.249"></a>
<FONT color="green">250</FONT>                    }<a name="line.250"></a>
<FONT color="green">251</FONT>                    input.close();<a name="line.251"></a>
<FONT color="green">252</FONT>            }<a name="line.252"></a>
<FONT color="green">253</FONT>    }<a name="line.253"></a>
<FONT color="green">254</FONT>    <a name="line.254"></a>
<FONT color="green">255</FONT>    <a name="line.255"></a>




























































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